Anti-foam agents in separation of olefines from solvent



April 1959 c. M. FIIN'IGAN ETAL 2,884,474

ANTI FOAM AGENTS IN SEPARATION OF OLEFINES FROM SOLVENT Filed April 23. 1956 United States Patent ANTI-FOAM AGENTS IN SEPARATION OF 'OLEFINES FROM SOLVENT Charles M. Finigan and John Phillip Spehar, Sarnia, 0n-

tario, Canada, assignors to Polymer Corporation Limited, Sarnia, Ontario, Canada, a corporation of Canada Application April 23, 1956, Serial No. 579,794 12 Claims. (Cl. 260-6815) This invention relates to anti-foam agents. More particularly, it relates to certain anti-foam agents particularly suited for breaking foam in a specific industrial application.

It is now well known that butadiene-l,3 is an especially ,valuable commercial chemical since it can be polymerized, either alone or together with other materials to form a variety of polymeric materials; an example is the copolymerization of butadiene-1,3 and styrene to form a synthetic rubber known as GR-S. Butadiene-1,3 may be conveniently formed by the dehydrogenation ofn-butylene "using, for .example, :a calcium nickel phosphate catalyst, of the type disclosed'in U. S. Patent 2,442,320, issued May 25, 1948, to Andrew J. Dietz'ler etal., in the presence of steam. The product of the dehydrogenation usually :contains about 18 to 25 weight percent butadiene-l,3,with the remainder .being ,n-butyleneand other hydrocarbons. ln

order to obtain substantially pure butadiene-l,3 for use 'as a 'polymerizable --monomer, it is therefore neces-saryto separate the butadiene-l,3 from the contaminants.

One satisfactory method of separating olefinic hydrocarbons containing at least four carbons in the olefinic chain, for example, butadiene-l,3, is by thoroughly mixing the hydrocarbon stream with a solvent "selective for .such olefinic hydrocarbon and thenpassing the mixture to a settler where the hydrocarbon-rich-solyent separates "from the other hydrocarbons. Suitablesolvents include those which are :ammoniacalsolutions-of copper-ions with an .anion capable of :forming cuprous 'salts soluble in such solvent. Examples of such anions include formate, acetate,

maleate, sulfate, chloride, etc. Thesolutions may be aqueous or aqueous alcoholic solutions of methanol, ethanol or propanol. An example of such solvent is aqueous .copper ammonium acetate. A-series of such .rnixer-settlers ,.may be used in which case=solvent passes in 10116 the hydrocarbon stream passes in the opposite direction. After :passage through such a series of mixer-settlers the solvent stream is enrichedinithe olefinicihydrocarbon and is relatively free of other hydrocarbons. 'Before it .can be used, the olefinic hydrocarbon must be :separatedfrom the solvent; and this is usually done by heating the rich solvent in a desorption column where the olefinic hydro carbon is removed in vapour form.

"It'is found that, in the "desorption step for the removal of buta'diene-l,3 from an amm'oniacal :copper rion solvent, excessive foaming, 'which hampers the efficiency ,of the process, is frequently encountered.

It "is therefore an *object of the present invention-to "in'is driven off in a desorber'tower.

direction :and

'disclose a compatible anti-foaming agent to be used -in I 2,884,474 Patented Apr. 28, 1959 face active ester of a fatty acid containing 12-18 carbon atoms. Particularly, it envisages the process of preferentially expelling, .by .heat, .the butadiene-l,3 dissolved in a copper ammonium acetate solvent which comprises inhibiting foam during ,said preferential .expulsion by the addition to said olefin-containing solvent, of a non-ionic surface active ester of a, fatty acid containing 12-18 carbon atoms.

In this specification the terms, anionic, non-ionic and cationic are used in their accepted meanings. Thus, the anionic compounds are those which are ionized in solution with the acive portion of the molecule being negatively charged and moving in solution towards the anode. The anionics consist principally of the sulfated and sulfonated compounds which can be subdivided into the following categories: alkyl-aryl sulfonates; alkyl sulfates; sulfated and .sulfonated amines and amides; sulfated and sulfohated esters and et hers; alkyl sulfonates; and miscellaneous types.

The cationic compounds .are those in which the active 7 part of the molecule is positively charged and hence moves in solutions towards the cathode. The cationics generally areweak in detergentpower vbut mainly have strong lubricating andgermicidal properties. They fall into two main classes: acid neutralizedtertiary amine salts; and quaternaryammonia compounds.

Those compounds which do not ionize in solution are known as non-ionics. They-are generally insoluble in water and are chiefly emulsifying agents. The two main types are esters and fethers, the ether sometimes being present in .a groupef .polyalcohols on ethylene .oxide. The hydrogphilic part of .the =chain;may bean acid, alcohol, phenol, amide or amine.

In the testing of various agents for anti-foam activity aunder conditions similar to actual operating conditions, the following procedure was used:

Four hundred mls. of copper ammonium acetate solvent, containing dissolved butadienewas introduced into a calibrated tube. Butadiene-l,3, saturated with am- ;monia, was then passed through ;a 'fritted glass disc and ,into the copper ammonium acetate solvent at a rate suffilcient to produce a 1000 00. columnof foam. Then, without varying the flow of the butadieneilB, one drop of the anti-foam agent under test, approximately p.p.m. was introduced at the top of the column. The eliectiveness of the agent was based on the rate 'offoam destruction, with the time recorded for the half and complete foam :destruction. The results for 8 l compounds are given in Tabled, below. The-name in brackets. indicates the manufacturer of the tradenamedproduct.

The apparatus used in the determination is shown in -.somewhat diagrammatic form in the drawing.

-Butadiene-1,3, which is .drawn from the conventional butadiene-lj extraction .unit ,hereinbefore described and .known rate and passes into' 'bubbleril, which contains concentrated ammoniumhydroxide. Thus, the butadisolvent, atom is formed.

TABLE I enters by inlet 6., through a sintered glass disc 7. Thus,

as the butadiene-lfi enters the copper ammonium acetate Efiects of anti-foam agents on copper ammonium acetate-hydrocarbon foam I. ANIONIO Time of Foam Destruction No. Trade N ame Chemical Name (Seconds) Remarks Half Complete (A) ALKYL ARY L SULFONA'IES Acto 450 (Esso Standard Oil Co.) An alkyl aryl sulfonate -Q 40 180 pr eclpltgte orme Aerosol 08 (American Cyanimid). Isopropyl naphthalene sodium sulfonate.- exfeess to break I 1 v am. Aleowfif ANS (Arnold Hellman and Sodium alkyl naphthalene sulfonate 7 180 poor. 0. c. t Alkanol WXN (Du Pont) Sodium Alkaryl sulionate 180 pr ecipltgte OIIIlG L Alrosperse 40 K (Alrose Chemical Co.) Alkyl naphthalene sodium sulfonate ineffective. Arkolene (1N (ArkansasCcJ Ammonium Alkyl aryl sulfonate 25 180 potor tirecipllt 1 a e orme Dimol 11 (Quaker Chemical Products Alkyl aryl Sulionate; inefiective.

orp. Merpentine (Du Pont) Modified alkyl naphthalene sulfonate 12 170 foamed. Migcowet lfia (Morton-WithersChemical Alkylnaphthalene sulfonate 5 i 170 Do.

0. Neomerpin N (Du Pont) Alkylated Naphthalene sulfonic acid r. inefiective. N eomerpin (Du Pont) Derivative of alkyl naphthalene sulfonate 180 poor, foamed. Novonacco (National Aniline of Allied Modified sodium alkyl naphthalene sul- 6 180 excess required Chemical). fonate. I I to complete. Santomerse 30 X (Monsanto) .1 Alkyl aryl sodium sulfonate 7. 180 foamed- Santomerse 3 (Monsanto) Alkyl aryl sodium sulfonatm; 9 180 D0.

Sultramin N (UltraChemical Works)--- Sofdimm cslailt of dialkylnaphthalene sulineffective.

on c a Sulframin KE (Ultra Chemical Works). Alkyl Aryl snlfnn aha 77 Do. Tiltgzisle SA (Titan Chemical Products Sodium alkyl naphthalene sull'onate 7 180 foamed. I

(B) ALKYL SULFATES 18;-.- Avitex AD (Du Pont) Suliated alcohol derlvative- 45 180 poor. 1D-.. Alrosene W (Alrose Chemical 00.) Salt of a secondary alcohol sulfate 3 10 foamed. 20. Duponol D (Du Pont) Mixed alcohol sodium sulfate 5 30 i 21..... Merpol C (Du Pont) Fatty alcohol sodium sulfate plus s 6 180 ex es s rei uired o rea foam. 22. Sulframin DR (Ultra Chemical Works). Sodium Salt of an hydroxyl alkyl amide 2 5 alcohol sulfate.

(C) SULFONA'IED AND SULFATES AMIDEB AND AMINES Alrosol B (Alrose Chemical Co.) Fatty alcohol amide condensate 5 180 foamed. Duponol 08 (Du Pont) Fatty alcohol amine sulfate composition..- 7 22 Some precipitate formed i with excess. 25 Igepon CN-42 (General Dyestufi Corp.)- Sodium-N-cyclohexyl-N-palmitoyllaurate. 9 15 excess foams. 26 Miagon RK Cone. (Miranol Chemical Sulfonated fatty acid amide derlvative...-. 12 180 Do.

0. 1 27"... Sequestrene A A (Ah-ose Chemical 00.). Tetra ammonium salt of ethylene diamine ineffective.

\ tetraacetlc acid.

(D) SULFONATED AND SULFATED ESTERS AND ETHEBS 28... Aerosol AY (American Cyanamid) Dlamyl ester oi sulfosuccinic i exicess to break' cam. 29 AerosolMA (American Cyanamid) Dlhexyl ester of sodium sulfosucclnic acid D0. 30-.- Aerosol 0T (American Cyanamid) Dicctyl ester otsodium snlfosuccinic acid Do. 31- Carbase Emulsifier (Carlisle Chemical A sulfonated petroleum base with added 25 Do. 7 Works, Inc). emulsifier. 32"--- Dyjnesol) F20 (Amalgamated Chemical Sulfonated polyester ofanaliphatlcalcohol ineffective. v orp. 33.....- Nopco 2031 (N opco Chemicals) Snll'ated hydroxy steeric acid foams.

A (E) ALKYL SULFONATES 34.-. Compound 8-S (Johnson-March Corp.) flodiium salt of condensed alkyl sulionic foams.

. ac 35.--.- Petrowet R (Du Pont) Aliphatic hydrocarbon sodium sulfonaten 3 15 prfecipitgte orme (F) MISCELLANEOUS TYPES 30 Aresklene 375 (Monsanto). Dibutyl phenol sodiu disulfn ineffective. 37..-.. Arkolene WX (Arkansas Co.) Sodium alkyl aryl sulfonate plus poly- 4 180 foam and preglycol. gipitatie orme 38..... Lomar PW (J'aques Wolf& 00.) flosdlllum felt of condensed naphthelene foams.

' one e. i 39- N ekal N F (General Dyestufl Corp.) Sodium alkyl naphthalene snl ineflectire.

seam

TABLE I-'Continued :Eficct of anti-foam agents on copperammonium acetate-hydrocarbon foam Time of Foam Destruction No. P Trade Name Chemical Name (Seconds) Remarks not Complete II. CATIONICS klokaterg'e (Commercial Solvents Asubstituted oxazoline. 50: 180 orp; 'Auine O (Lucidol Div.,'Novadel-Agene heterocyclic tertiary amine 13 45.

orp. Ethorneen S-IO (Armour & Co.) Tertiary amine loams. Ninol 737 (N inol Laboratories) Mixed fatty acid alkanol amine ,promotesioam.

uatronyx (Onyx Oil andChemlcal 00.). Quaternary ammonium compound foams.

III. NONIONICS '4'5 'E%uIph)or EL-719 (General fDyestulflE TPolyoxyethylated vegetable oil Q 3 11 good.

* orp. 46"--. Ellllph)01 N430 (General Dyestufl Polyoxyethylated fattyacid 7 20 Do.

orp. v 147*. Eiulsiiger 610A (General Dyestufl Polymerlzed higher glycol fatty acid ester- 3 180 exgess to break J orp. 4 o '48- Nonisol 1'00 EAlrose Chemical 00% A polyethylene glycol of lauric acid 5 good. '49 -Nonisol 300 Ahose Chemical Co. 'Poltyethylcng glycol (M.W. 400) ester of 1 '2 Do.

. s earic aci Span 20 (Atlas Powder Col) Sorbitan monolaurate "21 15 Do. Span 80 (Atlas Powder C0,)- Sorbitan oleate 10- 40 B0. Span 85 (Atlas Powder 00.)- 'Sorbitan trioleate .8 Do. Tween 20 (Atlas Powder C J. polyoxyethylene sorbitan monolaurate 5 l7 JDo. Tween 40 (AtlasPowder 00.)- polyoxyethylene sorbitan monopalmltate- -l0 180 fair.

Tween (Atlas Powder 00.)- polyoxyethylene sorbltan monostearate 10 -25 good.

IV. SILICONE 56 Dow Corning Anti-foam A A silicone- 18 180 unsatisfactory.

Dow Corning Fluid 200 d 360 Do. Linde Silicone X Do. G.E. Anti-foam- 25 180 Do.

60 Aerounti-foam H (American Oyan- 7 360 unsatisfactory.

ami Atlas ORL #32334 G 656 15 75 fair.

15 180 unsatisfactory. no efiect no effect Flux Oil petroleum oil 22 unsuitable. Hercules Defoamer 4 (Hercules Powder 2 7 fair.

0. Nalco X285 (National Aluminate Corp). 3 Do. Nil 7 20 good.

22 90 fair.

1 2 forms a precipitate. Polyethylene glycol (M.W. about 400) no efiect Polyglycol 25] unsatisfactory.

It is seen from the above table that only a limited TABLE II number of agents are suitable for use as anti-foam 60 Efiective annzfoam agents agents in the system contammg aqueous copper ammonium acetate and butadiene-1,3. These agents may be Tra N m Ch mi al Name Class classified broadly as non-ionic surface active esters of a fatty id containing 12 18 carbon atoms 1 Emulphor EIF719 Poliyoxyethylated vegetable non-ionic.

In the tests described above, it is seen that only a 65 2 Emulphor N430 Polyoxyethylated fatty acid. Do. representative group of compounds from each class was Pglgefihyleneglyclmm chosen for test purposes. As a general rule, a compound N011i501300 polyolyethylene glycol Do- (M.W. 400) ester of stearic was considered unsatisfactory if any or all of the followacid. ing events occurred: 1) the foam breakage was negligible 58%;: figgi g zffff fg8:

1 or 1 an no ea e 0. or slow, (2) a prec pitate or scum was formed when the Tween 20 polyoxyethylene Sorbmn compound was added to the system; (3) an excess of 9 T 4 nllonolaufiaiie.

the agent under test produced its own foam. The agents ween 0 {,fg;; sorbitan which were considered suitable are listed separately be- Tween 60 fi$g ggggfg 50mm low in Table II. 7

7 While it is not desired to ticular theory,

taining 12-18 carbon atoms.

be limited to or by any pary it is believed that there may be some cor relation between the chemical structure of the effective) anti-foaming agents and thecopper ammonium acetatei v 4. Thev process as claimed 'inclaim 2 xwherein the non iomc surface active agent is a acid containing 12-18 carbon atoms. a

solvent. Most --of the compounds contain fatty acid face active agent isapolyoxyethylated vegetable oil'in' groupings which correspond to the acetate grouping in which the polyoxyethylene has a maximum molecular; the solvent and/or amine groupings correspondingto weight of about 400. a g the ammonia in the solvents. Thus thelsilicons and the 1" 6. The process of claim 2 wherein the non-ionic sur-' glycols are inefiective anti-foam agents in the present face active agent is polyoxyethylene glycol ester of stearic case. g g p lo acid in which the polyoxyethylene has a maximum mo- What we claim is: r a g lecular weight of about 400;

1. In the process of expelling, by heat, an olefinic hy- '7. The process of claim 2 wherein the non-ionic surdrocarbon having at least 4 carbon atoms in the olefinic face active agent is sorbitan monolaurate; t v chain, said hydrocarbon being dissolved in a solvent com- 8. The process as claimed in claim 2iwherein the nonprising an ammoniacal solution of copper ions with an 5 ionic surface active agent is a sorbitan oleate. anion capable of forming cuprous salts soluble in said 9. The process as'claimed in claim 2 wherein the nonammoniacal solution, the olefinichydrocarbon being re ionic surface active agent issorbitan trioleate. covered in vaporized state to leave a stripped solvent and 1D. The process as claimed in claim 2 wherein the nonthe stripped solvent being recovered in liquid state, said ionic surface active agent is polyoxyethylene sorbitan, it stripped solvent having dissolved therein foam product monolaurate wherein the polyoityethylenehasamaximum ing materials, the improvement which comprises inmolecular. weight of about 400. hibiting foam during said expulsion by the addition, to g 11. The process as claimed in clairn 2 wherein the i said olefin-containing solvent, of a nonsionic surface active non-ionic surface active agentis polyoxyethylene sorbitan ester of a fatty acid containing 12-18 carbon atoms. monopalmitatein which the polyoiryethylene has a maxi- 2. In the process of expelling, by heat, the butadiene mum molecular weight of about400. 1,3 dissolved in an aqueousv copper ammoniumacetate 12. The process as claimed in claim 2 wherein the solvent the butadiene-1 ,3 being recovered in a liquid non-ionicsurface active agentispolyoxyethylene sorbitan state to leave a stripped-solvent, said stripped solvent monostearate in which e polyoxyethylene has a maxi having dissolved therein foam producing materials, the mum molecular weight of about 400. improvement which comprises inhibiting foam during said s expulsion by the addition, to said butadiene-1,3-contain- References Cited in the file of this P Q ing solvent, of a non-ionic surface active agent ester UNITED STATES PATENTS of a fatty acid containing 12-18 carbonatoms. t

3. The process of claim 2 wherein the non-ionicsur- Eggs: 2? i- ;fi

face active agent is a sorbitan ester of a fatty acid con I e i polyglycol ester of a fatty,

5, The process of claim 2 wherein the non-ionic sur- 

1. IN THE PROCESS OF EXPELLING, BY HEAT, AN OLEFINIC HYDROCARBON HAVING AT LEAST 4 CARBON ATOMS IN THE OLEFINIC CHAIN, SAID HYDROCARHON BEING DISSOLVED IN A SOLVENT COMPRISING AN AMMONIACAL SOLUTION OF COPPER IONS WITH AN ANION CAPABLE OF RORMING CUPROUS SALTS SOLUBLE IN SAID AMMONIACAL SOLUTION, THE OLEFINIC HYDROCARBON BEING RECOVERED IN VAPORIZED STATE TO LEAVE A STRIPPED SOLVENT AND THE STRIPPED SOLVENT BEING RECOVERED IN LIQUID STATE, SAID STRIPPED SOLVENT HAVING DISSOLVED THEREIN FOAM PRODUCING MATERIALS, THE IMPROVEMENT WHICH COMPRISES INHIBITING FOAM DURING SAID EXPULSION BY THE ADDITION, TO SAID OLEFIN-CONTAINING SOLVENT, OF A NON-IONIC SURFACE ACTIVE ESTER OF A FATTY ACID CONTAINING 12-18 CARBON ATOMS. 